1. Field Of The Invention
This invention relates to a support structure for under water and to a method for making such a support structure.
Foundation works in under-water constructions are usually complicated and expensive. When a support structure is to be placed upon the bottom of a harbor, river, at sea, or in a watercourse, where piledriving is not required, a bed of gravel or crushed material (macadam) is usually laid upon the bottom. This bed must be carefully levelled, so it becomes even and horizontal. This is difficult work in view of the depth of the water, which may be considerable, and the reduced sight at such depth.
Gravels and crushed stones have different angles of repose, depending upon the size and the shape of the particles (the fraction), as well as the nature of the rock material. If a mound of macadam is subjected to a modest, evenly applied load, say 5 tons/square meter, the natural slope, determined by the angle of repose (the angle of maximum slope at which a heap of loose solid material will stand without sliding) will remain unchanged under the load. The macadam only becomes slightly compressed. If macadam is distributed through a tube upon a horizontal substratum a conical mound is obtained, which covers a circular base area, and has a sloping envelope surface with an even contour. This is true, even if the bottom is un-even or slightly inclined.
The object of the present invention is to simplify the forming of such mounds of friction material in exactly desired positions, and to utilize the same as foundations for support structures.